1 + 1 = 1
When creating marriage, God said that the two shall become one flesh. Both husband and wife have responsibilities which reflect those of Christ (husband) toward the church, and the church (wife) toward Christ. The model is perfect, but the two people coming together in the same space at the same time are both sinners and have many differences. This situation creates one of the greatest tests for the man and the woman as they work together to become "one flesh."